Trapping Africa's animals — on camera

This great shot of a cheetah family comes from the Serengeti camera traps set up by University of Minnesota researcher Ali Swanson. The cameras are activated by heat and motion, and Swanson uses the help of citizen scientists to sort through the many, many pictures and identify species — a process that helps the scientists learn how those other big animals interact with the prides of lions that live in Tanzania's Serengeti National Park.